The Agent's Guide to Maintaining DID Health Quarterly
A quarterly DID maintenance checklist for insurance agents — audit, CNAM verification, attestation review, and reputation tracking that keeps pools healthy.
TL;DR
A DID (Direct Inward Dial) pool is not set-and-forget. The agencies holding stable answer rates over 12+ months run a roughly 90-minute quarterly maintenance cadence: inventory pull, cross-carrier reputation check, CNAM verification, STIR/SHAKEN attestation review, branded caller ID renewal, call-pattern audit, compliance hygiene, and documentation. This post is the exact sequence, with what to look for at each step.
A DID pool requires maintenance. Carrier reputation scores drift, CNAM (Caller ID Name) records get out of sync, attestation levels change when carriers update their platforms, and branded caller ID registrations expire. The agencies that hold stable answer rates run quarterly maintenance — roughly 90 minutes of work, four times a year — that catches drift before it becomes a pool-wide problem.
Why quarterly, not monthly or annually
Monthly audits produce noise — individual carrier scores fluctuate day to day based on call volume, recipient behavior, and analytics vendor updates. Responding to short-term noise leads to unnecessary DID retirement.
Annual audits miss the window for easy remediation — a number drifting in Q2 is salvageable with CNAM fixes and pacing adjustments; the same number left until Q4 is usually beyond recovery.
Quarterly maintenance catches meaningful drift early while filtering short-term noise. The cadence also aligns with the rhythm of most regulatory changes — FCC rule updates, carrier policy changes, and STIR/SHAKEN framework revisions tend to land on roughly quarterly cycles.
The quarterly checklist
A 10-20 DID pool takes roughly 90 minutes the first time and 45-60 minutes each subsequent quarter.
1. Pull current inventory
Produce a spreadsheet listing every DID currently in use with:
- DID (full 10-digit number)
- Carrier / SIP provider
- Campaign or producer assignment
- Date acquired
- Initial CNAM registration
- Current monthly dial volume (approximate)
- Last quarter's health status
If the operation does not have this inventory, assembling it is the first quarter's work.
2. Run a cross-carrier reputation check
For each DID, check display status across the major US mobile carrier analytics networks — Hiya (used in various mobile deployments), TNS (Verizon and others), and First Orion. A DID can display differently across networks because each uses different analytics.
| Finding | Action |
|---|---|
| Clean on all three | Continue using, no action |
| Flagged on one carrier | Investigate cause, consider retiring if repeat offender |
| Flagged on two carriers | Pull from pool, schedule for retirement |
| Flagged on all three | Retire immediately |
Self-testing by dialing your own phone misses cross-carrier visibility — you only see what your carrier shows. A tool like LineShield surfaces the picture in one place.
"Every flagged call damages your entire number range's reputation." — pattern documented by Quo's analysis of VoIP number reputation, echoing the same concern raised repeatedly on r/VOIP and r/smallbusiness threads about shared inventory pools.
3. Verify CNAM display accuracy
CNAM is the text label that appears alongside the phone number on the recipient's screen. It is a per-carrier lookup, not a universal setting. Common CNAM problems found in quarterly audits:
- Displays "UNKNOWN CALLER" on one or more major carriers (registration lapsed or never propagated)
- Displays an outdated company name (agency rebranded, CNAM not updated)
- Displays "WIRELESS CALLER" or the LERG-default city name
- CNAM character limit truncated the display ("SMITH INSUR" instead of "SMITH INSURANCE") — CNAM is limited to 15 characters under industry convention documented by Numeracle's CNAM reference
Fix by reissuing the CNAM registration with the carrier or CNAM provider. Propagation takes 24-72 hours. See CNAM setup for insurance agents if this is new ground.
4. Review STIR/SHAKEN attestation levels
Every outbound call carries an attestation level from the originating carrier under 47 CFR § 64.6301: A (full), B (partial), or C (gateway). A-level is the target. Recipients' carriers factor attestation into spam-label decisions. TransNexus's STIR/SHAKEN reference covers the mechanics in detail.
What to check:
- Per-DID attestation level based on recent call logs
- Whether the carrier relationship supports A-level attestation (some reseller arrangements cap at B)
- Whether any DIDs have dropped from A to B in the last 90 days
If attestation has regressed, contact the carrier. Often the fix is re-signing a Known Customer Agreement or updating the carrier's caller ID database with current ownership documentation.
5. Confirm branded caller ID status
For DIDs enrolled in branded caller ID — programs operating under the framework the FCC addressed in its October 2025 call-branding FNPRM — confirm:
- Enrollment is current (annual renewal is typical)
- The registered brand identity matches current business records
- The logo meets current spec (resolution, format)
- The DID is properly associated with the brand in the registry
Letting an enrollment lapse silently erases the answer-rate lift.
6. Audit per-DID call pattern metrics
Pull the following from the dialer for each DID over the last 90 days:
| Metric | Healthy Range |
|---|---|
| Answer rate | >5% for cold outbound |
| Short-call rate (<6 sec) | <15% |
| Avg calls per day | <300 for cold |
| Abandonment rate | <1.5% |
| Days active in last 90 | >60 (indicates real use, not just rotation) |
Numbers falling outside these ranges warrant investigation — either they are flagged (see step 2) or the campaign using them is creating flag-inducing patterns. Abandonment specifically is capped by 47 CFR § 64.1200(a)(6) at 3% of live-answered calls.
7. Review consent and DNC hygiene
Quarterly maintenance is a natural checkpoint for compliance review:
- Internal DNC list synced across all dialing platforms and DIDs
- Consent records audited for completeness (any gaps in the timestamp/source trail?)
- State calling-hour rules current — for example, Florida F.S. 501.059 and similar state-specific statutes update periodically
- Reassigned Numbers Database checks logged for all cold-list dialing, preserving safe harbor under 47 CFR § 64.1200(m)
- Federal Do-Not-Call scrubbing against donotcall.gov and FTC TSR obligations under 16 CFR Part 310
A compliance audit failure discovered quarterly is manageable. The same failure discovered during enforcement action is not.
8. Document and plan
Close the quarter with a one-page summary:
- DIDs retired this quarter (and why)
- DIDs added and warming schedule
- Outstanding CNAM / attestation issues
- Flagged items to revisit next quarter
Trending this quarter over quarter reveals whether the pool is stable, drifting, or deteriorating.
A sample quarterly calendar
For an agency with a 15-DID pool across 3 producers:
| Week | Activity |
|---|---|
| Quarter start, week 1 | Run full audit. Identify flagged DIDs. |
| Week 2 | Retire unrecoverable DIDs. Acquire replacements. Begin warming. |
| Week 3 | CNAM re-registration on any DIDs showing display issues. |
| Week 4-6 | Replacement DIDs warming at graduated volume. |
| Week 7-8 | New DIDs deployed at full volume. Branded caller ID enrollment refreshed. |
| Week 9-13 | Steady state. Weekly spot-check of any at-risk DIDs from the audit. |
Between-quarter monitoring
Between quarters, a lighter weekly check catches fast-moving problems:
- Any DID with answer rate down meaningfully week over week
- Any DID showing new short-call spikes
- Any producer reporting "nobody answers these numbers anymore"
Those three signals warrant an immediate spot-check rather than waiting for the next quarterly review.
What "elite" quarterly maintenance looks like
The agencies with the most stable long-term deliverability do three things that less-disciplined operations skip:
They retire proactively. A DID showing early drift gets retired before it flags, not after. Retiring 2-3 DIDs per quarter as preventive maintenance costs less than letting 8 flag simultaneously.
They warm continuously. A small pool of DIDs is always in the warming phase, ready to replace retired numbers without disrupting producer capacity.
They treat CNAM as living infrastructure. Business name changes, office moves, and rebrands trigger immediate CNAM refreshes, not "we'll get to it."
Common failure modes
"I checked last quarter, should be fine." — Reputation drifts. A DID clean in January can flag by April with no change in usage, simply because analytics models updated. This is echoed across r/VOIP reputation-management threads and VoIP.ms community forum discussions.
"The dialer says the number is good." Dialer built-in checks are not a substitute for cross-carrier reputation monitoring. Dialers rarely see the full picture.
"We'll fix CNAM when someone complains." By the time recipients complain, the CNAM damage has already suppressed answer rates for weeks.
"Warming takes too long." Warming takes 2-3 weeks. Replacing a burned pool takes 60-90 days. The math is not ambiguous.
See the companion pieces on dialer tech stack, outbound benchmarks, and buying vs. porting numbers.
FAQ
How long should a quarterly audit take? First one: 2-3 hours to establish baseline inventory. Subsequent quarters: 45-90 minutes for a typical agency pool.
Do I need to retire a DID that is flagged on only one carrier? Depends on the carrier and how long the flag has been present. A flag that appeared this quarter and cleared in 30 days can probably stay. A flag that has persisted for 60+ days should trigger retirement planning.
Can I recover a flagged DID? Sometimes. Mild flags from conservative campaigns can clear in 30-90 days if the number sits idle. Severely flagged DIDs rarely recover — replacement is usually faster and more reliable. First Orion's call-branding guidance covers remediation pathways.
What if I do not have historical data to compare against? The first quarterly audit establishes the baseline. Every subsequent quarter compares against the previous, and the picture becomes clearer within 2-3 cycles.
Should I audit inbound-only DIDs? Lighter-touch. Inbound-only DIDs do not generate outbound reputation signals but still benefit from CNAM verification and E911 address accuracy checks under 47 CFR § 9.11.
Who should own the quarterly audit in an agency? An operations lead or office manager, not a producer. Producers should be selling. The audit is infrastructure work.
How do I know when I have enough DIDs? Healthy operations carry 8-15 owned DIDs per producer for cold outbound, plus warm-follow-up DIDs that should not mix with cold. Below that range, reputation concentrates and flags accumulate faster.
How should I document reassigned-number checks? Log the RND query response per number per campaign with timestamp, as required to claim safe harbor under 47 CFR § 64.1200(m). Most modern dialers do this automatically but the records must be retrievable.
Is this all worth the effort? For operations running meaningful outbound, yes. The cost of a burned pool — in lost contact rate, recovery time, and replacement DIDs — is typically an order of magnitude larger than preventive maintenance.
Closing note
DID health is the boring, unglamorous layer of outbound performance. It is also the layer that separates agencies growing their outbound revenue from agencies watching it quietly erode. Ninety minutes per quarter is a rounding error against what a healthy pool produces in policies. Put it on the calendar.
Stop guessing. Run the audit.
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